3-indolepropionic acid

3-indolepropionic acid

Clinical data
Trade names	Oxigon
Synonyms	Conjugate base: Indole-3-propionate
ATC code	none
Legal status
Legal status	US: Unscheduled UN: Unscheduled
Identifiers
IUPAC name 3-(1H-Indol-3-yl)propanoic acid
CAS Number	830-96-6 Y
PubChem CID	3744
IUPHAR/BPS	4709
ChemSpider	3613 Y
UNII	JF49U1Q7KN
ChEBI	CHEBI:43580 Y
ECHA InfoCard	100.011.455
Chemical and physical data
Formula	C11H11NO2
Molar mass	189.21054 g/mol
3D model (JSmol)	Interactive image
Melting point	134 to 135 °C (273 to 275 °F)
SMILES C1=CC=C2C(=C1)C(=CN2)CCC(=O)O
InChI InChI=1S/C11H11NO2/c13-11(14)6-5-8-7-12-10-4-2-1-3-9(8)10/h1-4,7,12H,5-6H2,(H,13,14) Key:GOLXRNDWAUTYKT-UHFFFAOYSA-N

3-Indolepropionic acid (IPA), or indole-3-propionic acid, is a potent neuroprotective antioxidant and plant auxin that is being studied for therapeutic use in Alzheimer's disease. It is endogenously produced by human microbiota and has only been detected in vivo when the species Clostridium sporogenes is present in the gastrointestinal tract. As of April 2016^[update], C. sporogenes, which uses tryptophan to synthesize indole and subsequently IPA, is the only species of bacteria known to synthesize IPA in vivo at levels which are subsequently detectable in the blood plasma of the host.

The neuroprotective, antioxidant and anti-amyloid properties of IPA were first reported by a group of investigators in July 1999, led by Dr Pappolla and Dr. Poeggeler at the University of South Alabama.

IPA is an even more potent scavenger of hydroxyl radicals than melatonin, the most potent scavenger of hydroxyl radicals that is synthesized by human enzymes. Similar to melatonin but unlike other antioxidants, it scavenges radicals without subsequently generating reactive and pro-oxidant intermediate compounds.